The Woodturner's Workshop

A Glossary of Woodturning Terms

A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z.

See seasoning

Not possessing the same properties in all directions (the opposite of isotropic). Because of its fibrous structure wood is anisotropic.

The inner bark. The carbohydrates, formed in the leaves by photosynthesis, flow down through the cells in the bast to feed the life processes of the tree.

A means of supporting a long thin spindle to help to stop it flexing in the centre.

The part on the lathe which slides along the bed and supports the T rest.

A rounded raised portion running around a spindle turning.

Beading tool
A small chisel (often square in section) used to form a bead.

The horizontal part of the lathe which connects the headstock and tailstock

The part of the tool which is ground to form the cutting edge.

Numerous small areas on the surface of the wood in which the fibres are distorted so as to produce elliptical forms somewhat similar to bird's eyes. Found in maple and sycamore, rare in other species.

The blank is the form the piece of wood takes when it has been prepared for turning. Typically this will be a round disc for a bowl or a similar face turning, or a relatively slender 'square' sectioned piece for turning between centres.

Bowl gouge
A gouge with a deep flute and a heavy cross-section. Its primary function is for face turning but it can also be used for spindle turning. It is most commonly ground with a 40- 60 bevel angle.

A rare tool (Sometimes known as a bruzz or a buzz) which has a 'V' section. A turner's bruzze has the bevels ground on the outside, whereas a carpenter's bruzze is ground on the inside.

Built-up work
A workpiece which is made by gluing together two or more pieces of wood.

The American term for a growth on a tree which we in Britain call a burr. See also: burr (1)

Polishing by friction. In woodturning this is usually carried out by holding a handful of shavings against the revolving workpiece. The shavings should come from the work being burnished.

Burr (1)
A large wart-like growth, with twigs sprouting from it, found on the trunk of a tree. Internally the wood tissue is very confused and usually contains numerous dormant bud formations. The wood cut from a burr usually shows very attractive figure and is very highly prized by turners.

Burr (2)
A fine upstanding strip of metal left on the edge of a tool after grinding or the use of a ticketer. (It is sometime called a wire edge.) This can be honed off but many turners make use of the burr on a scraper to produce a very fine finishing cut.

A measuring tool consisting of two curved arms connected at one end by a hinged type joint. In their simplest, traditional, form they can be used for both inside and outside measurements. In their modern form the hinge is sprung and the arms are connected midway by an adjustable screw. In this form inside and outside callipers are separate devices.

Cambium layer
A thin layer of specialised cells which lies between the inner bark and the sapwood. It is here that the growth of the tree takes place. New sapwood cells are formed on the inner side of the cambium, and new bark is formed on its outer side.

The parts in immediate contact with the workpiece when it is held in the lathe by both ends. Hence the expression 'turning between centres'. See also: cone centre, dead centre, drive centre, live centre and ring centre

Centrifugal force
The force with which a body revolving around a centre tends to fly away from that centre. The force which causes pieces to fly off when work is revolving on a lathe.

See split.

Checkered work
See laminated work

A woodturning tool with either a square or a rectangular cross-section which is ground with a double bevel. See also skew chisel and square nose chisel.

A device which holds the workpiece on then lathe. A chuck can take many different forms. See, for example, cup chuck, precision combination chuck, screw chuck, and scroll chuck.

The movable metal parts in a chuck which grip the tool or the workpiece.

Cone centre
A live or a dead centre with a cone shaped point in the tailstock used to support the workpiece. See also centres

A semicircular hollow running round a spindle turning.

Crotch wood
Wood which lied immediately below the fork of a tree. When this wood is sawn lengthways (ie parallel to the pith) it can produce exceptionally beautiful, fan shaped, figure. Because of its beauty crotch figure is greatly prized.

Cup chuck
A chuck with a deep recess into which a spigot on the workpiece can be driven.

Cup shake
A split formed by the separation of the wood fibres around a growth ring.

Dead centre
A cone centre which does not revolve with the work. See also centres

Deep fluted gouge
See bowl gouge

Dividing head
See index plate.

Drive centre
This is attached to the drive shaft in the headstock by either a morse taper or a thread. It both supports the wood and transmits the drive to it. Usually it has either two prongs or four prongs which are driven into the workpiece. See also centres

Dovetail recess
A recess with an undercut edge cut in a workpiece to accept the jaws of a chuck.

End check
A split on the end of a board.

End grain turning
Turning in the end of a workpiece, which has the grain running parallel with the axis of the lathe, the other end of which is held by a screw, or other type of chuck.

Exotic timber
Imported timber of a type not indigenous to Britain.

Circular plate held on the headstock spindle to which the workpiece is attached by screws.

Face turning
Turning workpiece held on a faceplate, or a chuck when the grain of the wood runs at right angles to the axis of the lathe.

Figure which is produced by wavy grain when quarter sawn. It appears as a rippled effect on the surface, eg ripple maple/sycamore. The term has come into use because such wood with this figure has traditionally been used for the backs of violins.

The pattern on the surface of the wood caused by the combination of such features as grain, growth rings, rays, tissue structure, colour, knots, burr, and, sometimes, defects.

Used to fill the grain when a smooth finish is required. It is applied after the primary sanding operation. The work may be sanded again after the application of the filler and before the final polishing .

The application of filler.

The shape of the ground end of a spindle gouge.

The final treatment of the work after the tool-work has been complete, eg sanding, filling and polishing.

A section of timber cut lengthwise from the trunk of the tree,

Fluted parting tool
A tool with a wedge shaped section which has a flute on the wider of the two edges.

Forstner bit
Forstner bits are similar to sawtooth bits but they are guided by their rims and do not have a centre point. As a consequence they cut flat bottomed holes which can overlap each other or the edge of a board. they do not cut as well as a sawtooth bit in end grain.

Four jaw chuck
A self-centreing chuck similar to the engineering type but with four jaws instead of three. These chucks are often known as scroll chucks because of the internal spiral grooves which move the jaws.

A cutting tool with a 'U' shaped cross-section used with the bevel rubbing. There are three main types: the roughing gouge, the spindle gouge and the bowl gouge. For the latter two of these some turners prefer the terms shallow fluted gouge and deep fluted gouge respectively. The reason for this is that bowl gouges can be used for spindle turning and spindle gouges can be used on face work.

The alignment of the cells relative to the long axis of the tree, straight, diagonal, interlocked and wavy grain.

Growth rings
Each of these rings is the result of one year's growth. The rings are often easy to distinguish because the wood produced in the later part of the year is darker than that produced when the sap rising.

The assembly fixed on the left-hand end of the bed of the lathe which provides the drive for the workpiece.

Heart shake
A split running radially away from the pith.

The fully developed wood which surrounds the pith. It is often darker in colour and harder than the sapwood which surrounds it. The cells in the heartwood are dead and have ceased to transport sap.

High speed steel (H.S.S.)
High speed steel; this is about 6 times harder than carbon steel. HSS tools should be ground on a 'white' (aluminium oxide grinding wheel).

To sharpen a tool by hand on a stone.

An interior split, or group of splits, in a block of wood - usually only found in larger sections. Probably due to over-quick drying. Unfortunately, often not discovered until work is in progress.

Hook gate
See Sizing tool

See high speed steel

Inboard turning
Face turning which is carried out over the bed of the lathe, ie on the right-hand of the headstock.

Index plate
A plate used to lock the drive-shaft into a series of pre-set regular positions. The plate is sometimes built into the lathe and sometimes is a separate attachment used for specific jobs.

Jacob's chuck
Originally a proprietary name for a type of drill chuck which can also be held in the headstock or tailstock of a lathe. It can be used to hold a small workpiece instead of a drill.

See seasoning

Lace bobbin drive
A drive centre with a recess in the outer end to accept a lace bobbin blank.

Laminated work
A workpiece constructed from glued-up blocks. It should be allowed to dry thoroughly after gluing and then turned with sharp tools at a slow speed because centrifugal force can cause the pieces to separate.

Live centre
A centre in the tailstock which revolves with the work. See also centres

A means of holding a workpiece (or workpieces) by use of a rod of wood or metal running through a central hole, as for toy wheels and napkin rings.

See moisture content.

Medium density fibre board - a man made material used as an alternative to wood.

Medullary rays
Bundles of cells which run radially between the pith to the cambium layer. They are much more easily seen in some woods, such as oak, than others. The tree uses these cells for the storage of nutrients.

Moisture content
The weight of the water in a sample of wood expressed as a percentage of the weight of that sample when it is completely dry. Often abbreviated to the M.C. of wood.

Moisture meter
An electrical instrument for determining the moisture content (MC) of wood. There are two types of meter. One type measures the electrical resistance of the wood, the other measures the dielectric property of the wood.

Morse taper
A standard taper on a drill chuck or lathe drive centre which enables the device to be removed from. or attached to, the relevant machine quickly and easily. Abbreviated to M.T.

See morse taper.

Natural edge
The lip of a bowl or a goblet which shows the outside of the tree - often with the bark in place.

An elongated 'S' shaped curve.

Outboard turning
Face turning which is carried out on an extension of the drive-shaft on the left-hand side of the headstock, ie the opposite side to the bed. Relative to the turner the workpiece will revolve in the opposite direction as compared with turning over the bed; as a consequence the drive spindle and attachments, such as a faceplate, require reverse threads.

Parting tool
For parting off, ie cutting off the waste, or dividing the workpiece into sections.

Pin chuck
A chuck with a wooden or, more usually, a metal pin which is jammed into a hole drilled in the workpiece.

See 'Bast'

The narrow channel in the innermost part of the tree, its trunk, each branch and twig,

Polyethylene Glycol (PEG)
A pharmaceutical product which is sometime used by wood workers to stabilise unseasoned timber. It is available in several grades - PEG 1000 is the grade used by wood workers. When unseasoned wood is submerged in a solution of PEG 1000 the PEG is drawn into the wood by the process of osmosis and replaces the water. Given sufficient time the PEG will replace all the water in the wood. After the wood is removed from the solution the PEG will set in the pores to prevent shrinking cracking and distortion.

Precision Combination Chuck
A popular proprietary chuck with attachments which can perform many of the functions performed by the chucks listed here. It work on the basis of expanding or contracting collets. Nowadays, scroll chucks are preferred.

A section of the workpiece in spindle turning which is left square, eg when turning legs for chairs or tables.

See tool rest.

Ring centre
A live or a dead centre in the tailstock which has a small point set in the middle of a ring. The point locates the centre whilst the ring bears on the surface of the workpiece thus limiting the penetration of the wood. This helps to prevent splitting and is particularly useful for built-up or split turnings. See also centres

Ring shake
See cup shake.

Roughing out gouge (or roughing gouge)
Used in spindle turning for reducing square stock to round section. It has a semicircular section and is ground square across. The bevel angle should be around 35 to 45. A roughing gouge is for spindle work and should not be used for face turning, eg on bowls.

Figure found in wood which has wavy grain, eg ripple sycamore. See also fiddleback.

Rough turning
There are two possible meanings for this expression.
• The reduction of a square piece of timber to a round section. This is done with a roughing gouge.
• The preliminary work on turning a bowl. A beginner should never use a roughing gouge for this.

This surrounds the heartwood. It transports the sap from the roots to the leaves.

Saw cuts
When a log is converted to boards it may be cut in a number of ways. The three terms most commonly encountered are:
• back sawn.
• through and through, and
• quarter sawn.
When back sawn the log is converted in such a way as to provide the maximum number of cuts tangential to the growth rings.
When quarter sawn the log is converted in such a way as to provide the maximum number of cuts radial to the centre of the log. Quarter sawn wood is usually more stable, ie less prone to warping, shrinking and splitting, than that produced by other cuts. Often, it also has a more attractive figure because of the oblique way in which the medullary rays are cut, particularly in oak, sapele, London plane (lacewood), and sycamore (fiddleback).
Through and through (often abbreviated to T & T or T/T) refers to boards produced by simply sawing through the log in a series of parallel slices. A log sawn this way will produce some back sawn boards, some quarter sawn boards, and some in between.

Sawtooth machine bit
A special type of bit only used for drilling wood. It makes a hole with a flat bottom except for a small centre mark. Sawtooth bits will cut end grain and cross grain.

Screw chuck
A chuck with a single screw fixed in the centre to which the workpiece can be attached.

Scroll chuck
A four-jaw chuck, now very popular amongst woodturners. So named because the teeth on the underside of the jaws engage in a raised spiral (ie scroll) on the back-plate. Movement of the back-plate causes the jaws to move in or out in unison.

The first step in the finishing process. A sealer is applied to the bare wood to act as a barrier to the ingress of moisture and dirt. It also serves as a grain filler and as a base for further finishing coats.

Drying green wood to a serviceable level.
• Air dried: dried by exposure to the air without the use of artifical heat.
• Kiln dried: dried in a kiln (or oven) with the aid of artificial heat.

Segmented work
See laminated work.

See split.

Shallow fluted gouge
See spindle gouge.

Shell augur bit
Used for drilling long holes on the lathes, eg in electric lamp stands.

Sizing tool (or Hook gate)
A hook shaped attachment to a square parting tool which enables the workpiece to be sized to a pre-set dimension. This is particularly useful when an operation of this sort has to be performed repeatedly.

Skew chisel
A chisel on which the cutting edge is not square to the sides of the tool.

Spalted wood
Wood which is in the first stages of fungal decay, ie rot. Very often it is made manifest by irregular dark, or black, lines which run through the material. It is most common in beech but is found in many other hard woods. The fungae require damp conditions in which to grow; when the wood is dried (below about 20% MC) the fungae die and the process ceases.

A parallel projection on the end of a workpiece which is made to fit into a recess of some kind, eg a socket in a chair seat or in a spigot chuck.

Spigot chuck
See cup chuck.

Spindle gouge
Used for shaping spindle work, eg for turning beads and coves. It has a cross section with a shallow arc; so is sometimes referred to as a shallow fluted gouge. The cutting edge is usually ground to a finger nail shape with a 30 - 40 bevel angle.

A longitudinal fissure in the wood. Terminology may vary from place to place but there can be said to be two types of split: namely, shakes and checks. Shakes can occur in three main ways:
• in the living tree, possibly due to wind stress;
• at the time of felling, due to impact; and
• shrinkage in the log before conversion.
Checks occur after conversion of the log and are due to shrinkage whilst the material is drying. See also: cup shake, heart shake, star shake, end check, surface check, through check and honeycomb.

Split turning
A technique used where two identical semicircular items are required. One method is to make a complete turning from solid stock and then saw the piece in half. A better way is to glue two pieces of stock together with a leaf of paper in the joint and then make the turning. When the turning is complete the paper allows the pieces to be separated.

Square (wood)
A sawn piece of timber which is roughly square in section and ready to be used in spindle turning.

Square nose chisel
A chisel on which the cutting edge is square to the sides.

Star shake
A group of splits running away from the pith in the form of a star.

Surface check
A split on the surface of the wood.

T&T (or T/T)
See saw cuts.

The movable assembly to the right of the headstock which slides along the bed.

The tapered end of a woodturning tool which fits into the handle.

Through check
A split which extends through a board from one surface to the other.

A round piece of metal used to form a burr.

Tool rest (or T rest)
Adjustable part of the lathe (usually a 'T' shape) which fits into the banjo and supports the turning tool whilst work is in progress.

Waney edge
A natural edge left by the outside of the tree on a sawn board.

Wire edge
See burr.

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Brian Clifford (March 1999)